WO2017067017A1

WO2017067017A1 - Liquid crystal display panel

Info

Publication number: WO2017067017A1
Application number: PCT/CN2015/093198
Authority: WO
Inventors: 崔宏青
Original assignee: 深圳市华星光电技术有限公司; 武汉华星光电技术有限公司
Priority date: 2015-10-23
Filing date: 2015-10-29
Publication date: 2017-04-27
Also published as: CN105137649B; US20170336686A1; CN105137649A

Abstract

A liquid crystal display panel (300) comprises an array substrate (302), a colored film substrate (303) and a liquid crystal interlayer interposed therebetween. A photoelectric functional layer is disposed on the surface, facing the liquid crystal interlayer or far away from the liquid crystal interlayer, of the colored film substrate (303). The photoelectric functional layer can influence the polarization state of a light wave and generate an electric shielding effect. Therefore, the photoelectric functional layer can serve as both a polarizer and an electric shielding layer, and integrate the two functions, thereby simplifying the whole manufacturing process of the liquid crystal display panel (300).

Description

Liquid crystal display panel

Cross-reference to related applications

The present application claims priority to Chinese Patent Application No. CN201510694979.1, filed on Jan. 23,,,,,,,,,,

Technical field

The present invention relates to the field of display technologies, and in particular, to a liquid crystal display panel.

Background technique

Regarding the electrical shielding technology of the display, the following three cases are generally present in the prior art.

The first case: for the Fringe field switching-Liquid Crystal Display (FFS-LCD), which is widely used, the pixel electrode and the common electrode are located on the lower glass substrate of the liquid crystal cell (array) Substrate), there is no electrode layer on the upper glass substrate (color film substrate). Therefore, when there is accumulation of static charge on the outer surface of the liquid crystal cell, an additional electric field is easily generated, which affects the arrangement of the liquid crystal molecules, thereby causing an abnormality in the display picture, that is, drawing. In this regard, a general treatment method is to additionally provide an electrical shielding layer on the surface of the upper glass substrate (color film substrate) for electrical shielding treatment. The material of the electrical shielding layer may be a conductive oxide such as indium tin oxide (ITO), antimony oxide, tin oxide, zinc oxide and other metals. An oxide or an alloy oxide or the like; a material of the electrical shielding layer may also be a nano conductive material such as carbon nanotubes; and the electrical shielding layer may also be a polymer conductive film, a conductive ink, conductive particles or a conductive rod or the like. The layer to which these materials are positioned may be located on the upper or lower surface of the color filter substrate, or in a layer structure of the polarizer, or in a glue layer in which the upper polarizer and the cover glass are bonded.

The second case: for a liquid crystal display device using an external touch structure, the electrical shielding layer can avoid the influence of the coupled electric field of the data driving electrode on the external touch signal.

The third case: for a liquid crystal display device using an in-cell touch structure, an electrical shielding layer is also indispensable, which can effectively shield the influence of an electrostatic cumulative electric field caused by external charge accumulation on a touch signal. The latter will cause a decrease in signal to noise ratio.

In the first case, the smaller the impedance value of the electrical shielding layer, the better: the small impedance means that the static charge accumulated on the surface of the screen can be quickly derived to avoid the interference of the electrostatic electric field. In the second case, the requirements for the electrical shielding layer are the same as in the first case: since the capacitive screen is separated from the display screen, the finger can touch the capacitive screen smoothly, and the scanning and detecting signals of the capacitive screen can be smoothly operated. It will be shielded by the electrical shielding layer located in the lower layer, in this way to avoid interference with the distortion of the liquid crystal molecules in the display screen, and the data signal of the display screen will also be coupled due to the presence of the electrical shielding layer located in the upper layer. A signal that affects the touch screen. In the above third case, the impedance requirement for the electrical shielding layer is different from the first case and the second case: since the touch function layer is embedded in the display screen, if the impedance of the electrical shielding layer is excessive Low, it will block the touch sensing of the finger, so that the touch sensitivity is greatly reduced, and even the touch function is lost; but if the impedance of the electrical shielding layer is too high, the noise can not be effectively isolated, and the signal-to-noise ratio is seriously degraded.

FIG. 1 shows a liquid crystal display panel 100 of the prior art. Referring to FIG. 1, the liquid crystal display panel 100 includes a lower polarizer 101, an array substrate 102 (including a thin film transistor array, a touch sensor, and a common electrode or a ground electrode 107), a liquid crystal interlayer (not shown), and a color film in this order from bottom to top. The substrate 103, the upper polarizer 104, and the electrical shielding layer 105. The electrical shielding layer 105 is electrically connected to the common electrode or the ground electrode 107 through the silver paddle 106. In this case, in the manufacturing process, the electrical shield layer 105 is first formed on the surface of the upper polarizer 104, and then the polarizer 104 is attached, and the silver paddle 106 is clicked. It can be seen that the liquid crystal display panel 100 shown in FIG. 1 has a complicated process, a large thickness, and a high cost, and at the same time, many steps are likely to cause errors.

2 is a partial enlarged view of the junction of the electrical shielding layer 105 of the liquid crystal display panel 100 of FIG. 1 and the triacetate layer 104.1 of the upper polarizer 104. As is clear from FIG. 2, in the liquid crystal display panel 100, the conductive shielding layer 105 includes a plurality of conductive polymers 105.1, and the entire electrical shielding layer 105 is disposed on the triacetate layer 104.1 of the upper polarizer 104. Figure 2 clearly shows the junction of the two.

FIG. 3 shows another liquid crystal display panel 200 in the prior art. The liquid crystal display panel 200 includes a lower polarizer 201, an array substrate 202 (including a thin film transistor array, a touch sensor, and a common electrode or a ground electrode 207), a liquid crystal interlayer (not shown), a color filter substrate 203, and electricity in order from bottom to top. The shielding layer 205 and the upper polarizer 204. The electrical shielding layer 205 is electrically connected to the common electrode or the ground electrode 207 through the silver paddle 206. In this case, in the manufacturing process, first, an electrical shielding layer 205 is formed on the upper surface of the color filter substrate 203 (for example, by vapor deposition or sputtering of an indium tin oxide (ITO) electrical shielding layer), and then silver is spotted. The paddle 206 is then attached with a polarizer 204. It can be seen that the liquid crystal display panel 200 shown in FIG. 3 has the same complicated steps, large thickness, and high cost, and at the same time, many steps are likely to cause errors.

In summary, in the liquid crystal display panels of the two prior art shown in FIG. 1 and FIG. 3, in addition to the inherent structure of the

upper polarizers

104 and 204, a layer of conductive polymer is additionally added. Layer 105 or metal oxide 205. Since the conductive polymer layer 105 or the conductive metal oxide 205 is added, a certain loss of transmittance is caused, so that the transmittance of the panel is lowered.

Summary of the invention

In view of the above problems in the prior art, that is, the impedance of the liquid crystal display panel in the prior art is difficult to control and the light transmittance is lowered, the present invention proposes an improved liquid crystal display panel.

In one embodiment, a liquid crystal display panel according to the invention includes an array substrate, a color filter substrate, and a liquid crystal interlayer therebetween, wherein on a surface of the color filter substrate facing the liquid crystal interlayer or in the A photo-electric functional layer is disposed on a surface of the color filter substrate remote from the liquid crystal interlayer, and the photoelectric functional layer can affect the polarization state of the light wave and can generate an electrical shielding effect. In this way, the photoelectric functional layer can be used as a polarizing plate or an electrical shielding layer, and combines two functions in one body, so that the process of the entire liquid crystal display panel is simpler.

In one embodiment, the optoelectronic functional layer is disposed as a metal wire grid structure at a position corresponding to the display region. The impedance of the metal wire grid structure layer in the active area (AA) can be controlled by the thickness of the metal layer. As a result, for the first case and the second case (lower impedance required) described in the background section, the thickness of the metal in the metal wire grid structure layer can be relatively thick. It is also possible to adjust the width of the metal layer, for example to increase the width of the metal layer. For the third case described in the background section (requiring a relatively high impedance), the thickness of the metal wire grid structure layer can be reduced, or the width of the metal wire grid layer can be reduced, thereby adjusting the impedance of the metal wire grid to a Moderate level.

In one embodiment, the optoelectronic functional layer includes a metal bezel in communication with the metal wire grid structure at a position corresponding to an edge of the display panel, the metal wire grid structure and the metal frame being simultaneously in the same layer Form a pattern. The metal communication layer (metal frame) outside the AA area can bring the advantage that the net charge accumulated on the surface of the display can be quickly derived from various points around the circumference, compared with the electrical shielding layer of the prior art. Conductive media have a faster rate of conduction.

In one embodiment, the metal bezel is electrically connected to a common electrode or a ground electrode.

In one embodiment, the metal frame is bridged to the bonding pad at the bonding circuit of the array substrate by a point silver pad, the bonding pad being connected to the external common electrode signal or ground signal through the flexible circuit board. .

In one embodiment, the metal wire grid structure is composed of a metal of Al, Mo, Au, Cr, or an alloy material thereof. The conductive properties of metal materials are different from those of general inorganic or organic materials. The conductive impedance is relatively small, and the thickness of the metal layer can be reasonably controlled to obtain a moderately sized impedance value.

In one embodiment, the metal wire grid structure is a single layer metal wire grid structure or a double layer metal wire grid structure.

In one embodiment, in the single-layer metal wire grid structure, at least two metal strips extending in parallel in the same direction are disposed on a surface of the color filter substrate, and adjacent metal strips are separated by a wire grid. The gaps have the same height in a direction perpendicular to the surface of the color filter substrate.

In one embodiment, in the double-layer metal wire grid structure, at least two metal strips and dielectric strips extending in parallel in the same direction are disposed on a surface of the color filter substrate, and the metal strip and the strip The dielectric strips are staggered without gaps, and are covered with metal strips on the surface of the dielectric strip remote from the color filter substrate.

In one embodiment, the metal strips have the same size in a direction perpendicular to the surface of the color filter substrate, the height of the dielectric strip being greater than the size of the metal strip.

In both cases, the polarization direction of the incident light mainly includes two cases parallel to the metal strip and perpendicular to the metal strip; the polarization direction of the reflected light mainly includes the case of being parallel to the metal strip; the polarization direction of the transmitted light mainly includes perpendicular to The case of metal strips.

The above technical features may be combined in various suitable ways or by equivalent technical features as long as the object of the invention can be achieved.

DRAWINGS

The invention will be described in more detail hereinafter based on the embodiments and with reference to the accompanying drawings. among them:

Figure 1 shows a liquid crystal display panel in the prior art;

2 is a partial enlarged view showing a joint portion of an electrical shielding layer and an upper polarizer of the liquid crystal display panel of FIG. 1;

Figure 3 shows another liquid crystal display panel in the prior art;

4 is a schematic structural view of a liquid crystal display panel according to the present invention;

Figure 5 shows an electrical shielding layer of a first embodiment of a liquid crystal display panel according to the present invention;

Fig. 6 shows an electrical shielding layer of a second embodiment of a liquid crystal display panel according to the present invention.

In the drawings, the same components are denoted by the same reference numerals. The drawings are not in actual proportions.

detailed description

The invention will now be further described with reference to the accompanying drawings.

Fig. 4 is a view showing the structure of a liquid crystal display panel according to the present invention.

Referring to FIG. 4, in one embodiment, a liquid crystal display panel 300 according to the present invention includes an array substrate 302, a color filter substrate 303, and a liquid crystal interlayer (not shown) therebetween. On the surface of the color filter substrate 303 facing the liquid crystal interlayer or on the surface of the color filter substrate 303 remote from the liquid crystal interlayer, a photoelectric functional layer is provided, which can affect the polarization state of the light wave while being capable of generating an electrical shielding effect.

Further, the photoelectric functional layer is disposed as a metal wire grid structure 304 at a position corresponding to the display region. There is a wire grid gap 305 between the metal wire grids 304. The optoelectronic functional layer includes a metal bezel 312 in communication with the metal wire grid structure 304 at a location corresponding to the edge of the display panel. Structurally, the metal wire grid structure 304 and the metal frame 312 can be simultaneously patterned in the same layer.

The electric field vector of the transmitted light of the wire grid structure is perpendicular to the wire grid, which we call P light (or TM wave), and the electric field vector of the reflected light of the wire grid structure is parallel to the wire grid. We call it S light (or TE). Light). Taking metal aluminum as the metal material of the metal wire grid structure as an example: the real and imaginary parts of the equivalent refractive index of the TE wave grating aluminum layer are relatively large, the aluminum layer is equivalent to the metal film, and most of the TE waves are reflected and absorbed; The equivalent refractive index of the TM wave aluminum layer is larger and the imaginary part is smaller. The aluminum layer is equivalent to the dielectric layer with weak absorption properties, and most of the TM waves penetrate. The periodic pitch of the metal wire grid is generally smaller than the wavelength of visible light, that is, it is a sub-wavelength metal wire grid.

The metal bezel 312 can be electrically connected to a common electrode or a ground electrode. Specifically, the metal bezel 312 can be bridged to the bonding pad 307 at the bonding circuit of the array substrate 302 by the point silver paddle 306. The bonding pad 307 can be connected to the external common electrode signal or ground signal through the flexible circuit board. As is clear from FIG. 4, the bonding pad 307 can be located in the vicinity of the data driving circuit 311.

In terms of material composition, the metal wire grid structure 304 may be composed of a metal of Al, Mo, Au, Cr, or an alloy material thereof. The conductive properties of metal materials are different from those of general inorganic or organic materials. The conductive impedance is relatively small, and the thickness of the metal layer can be reasonably controlled to obtain a moderately sized impedance value.

In different cases, the metal wire grid structure 304 may be a single layer metal wire grid structure or a double layer metal wire grid structure.

Fig. 5 shows an electrical shielding layer of a first embodiment of a liquid crystal display panel according to the present invention. In the first embodiment, the metal wire grid structure 304 is a single layer metal wire grid structure. In the single-layer metal wire grid structure 304, At least two metal strips 304.3 extending in parallel in the same direction are disposed on the surface of the color filter substrate 303, and the adjacent metal strips 304.3 are separated by a wire grid gap 305. The metal strips 304.3 have the same height in a direction perpendicular to the surface of the color filter substrate 303. As can be clearly seen in FIG. 5, the polarization direction of the incident light 310 mainly includes two cases parallel to the metal strip 304.3 and perpendicular to the metal strip 304.3; the polarization direction of the reflected light 308 mainly includes the case parallel to the metal strip 304.3; The direction of polarization of light 309 primarily includes the case perpendicular to metal strip 304.3.

Fig. 6 shows an electrical shielding layer of a second embodiment of a liquid crystal display panel according to the present invention. In the second embodiment, the metal wire grid structure 304 is a two-layer metal wire grid structure. In the double-layer metal wire grid structure, at least two metal strips 304.2 and three dielectric strips 304.1 extending in parallel in the same direction are disposed on the surface of the color filter substrate 303, and the metal strips 304.2 and the dielectric strips 304.1 are staggered without gaps. On the surface of the dielectric strip 304.1 remote from the color filter substrate 303, a metal strip 304.2 is again covered. The dielectric strip 304.1 is light transmissive. There is a gap between the two strips of metal strips 304.2 of the first layer, which gap is filled by the dielectric strips 304.1; a gap 313 is interposed between the metal strips 304.2 of the second layer. Looking at Fig. 6, it can be clearly seen that the metal strips 304.2 have the same size in the direction perpendicular to the surface of the color filter substrate 303, and the height of the dielectric strips 304.1 is larger than the size of the metal strips 304.2.

It can also be clearly seen in FIG. 6 that the polarization direction of the incident light 310 mainly includes two cases parallel to the metal strip 304.2 and perpendicular to the metal strip 304.2; the polarization direction of the reflected light 308 mainly includes the case parallel to the metal strip 304.2; The polarization direction of the transmitted light 309 mainly includes the case of being perpendicular to the metal strip 304.2.

Comparing the above two cases: in a single-layer metal wire grid structure, there is only one metal wire grid layer on the same transparent substrate surface; in the double-layer metal wire grid structure, on the same transparent substrate surface, there are two kinds Metal wire grid layers of different heights are staggered. In terms of the process technology alone, the process of the double-layer metal wire grid structure is simpler.

In summary, the present invention provides a polarizing plate of a nano metal wire grid structure, which may be a single layer metal wire grid structure or a double metal wire grid structure. The metal wire grid structure is located on the upper glass substrate of the liquid crystal cell, that is, the color filter film substrate. The metal wire grid structure may be located on the upper surface of the color filter film substrate or on the lower surface of the color filter film substrate. At a position corresponding to the display edge region (not showing the window opening region) of the color filter film substrate, the region connected to the metal wire grid structure retains a planar metal layer (ie, a metal frame), and the planar metal layer region can be used to dot silver The paddle is then connected to the bonding pad of the lower glass substrate on the bonding IC region. The bonding pad can be connected to the external motherboard circuit through a flexible circuit board, and the bonding pad can be connected to the common circuit board through the flexible circuit board. The electrode signal can also be connected to a ground signal.

The metal wire grid structure for polarization is located only in the window area of the display (ie, the AA area, Active area), and the metal substrate of the upper substrate corresponding to the area other than the AA area is provided with a metal layer that communicates with each other ( That is, a metal frame), which can be formed together when the metal wire grid pattern is formed in the AA region. The peripheral metal layer may be connected to the common electrode or the ground electrode of the lower substrate through the conductive silver paste.

The liquid crystal display panel according to the present invention brings many advantages:

(1) The metal wire grid structure layer can be used as a polarizing plate or an electrical shielding layer, and combines two functions in one body, so that the process of the entire liquid crystal display panel is simpler.

(2) The impedance of the metal wire grid structure layer in the active area (AA) can be controlled by the thickness of the metal layer. As a result, for the first case and the second case (lower impedance required) described in the background section, the thickness of the metal in the metal wire grid structure layer can be relatively thick. It is also possible to adjust the width of the metal layer, for example to increase the width of the metal layer. For the third case described in the background section (requiring a relatively high impedance), the thickness of the metal wire grid structure layer can be reduced, or the width of the metal wire grid layer can be reduced, thereby adjusting the impedance of the metal wire grid to a Moderate level.

(3) The metal communication layer (metal frame) outside the AA area can bring the advantage that the net charge accumulated on the surface of the display can be quickly derived from various points around the circumference, compared with the electrical shielding layer in the prior art. The conductive medium used has a faster conduction rate.

Although the invention has been described herein with reference to specific embodiments, it is understood that these embodiments are merely illustrative of the principles and applications of the invention. It is understood that many modifications may be made to the exemplary embodiments, and other arrangements may be made without departing from the spirit and scope of the invention as defined by the appended claims. It will be understood that the different dependent claims and the features described herein may be combined in a manner different from that described in the original claims. It will also be appreciated that features described in connection with the individual embodiments can be used in other described embodiments.

Claims

A liquid crystal display panel comprising an array substrate, a color filter substrate and a liquid crystal interlayer therebetween

Wherein, a photoelectric functional layer is disposed on a surface of the color filter substrate facing the liquid crystal interlayer or on a surface of the color filter substrate remote from the liquid crystal interlayer, and the photoelectric functional layer can affect a polarization state of the light wave At the same time, it can produce an electrical shielding effect.
The liquid crystal display panel according to claim 1, wherein the photoelectric functional layer is provided as a metal wire grid structure at a position corresponding to the display region.
The liquid crystal display panel of claim 2, wherein the optoelectronic functional layer comprises a metal bezel in communication with the metal wire grid structure at a position corresponding to an edge of the display panel, the metal wire grid structure and the The metal frame simultaneously forms a pattern in the same layer.
The liquid crystal display panel according to claim 3, wherein the metal bezel is electrically connected to a common electrode or a ground electrode.
The liquid crystal display panel according to claim 4, wherein the metal frame is bridged to the bonding pad at the bonding circuit of the array substrate by a silver pad, the bonding pad passes through the flexible circuit board and the outside The common electrode signal or the ground signal is connected.
The liquid crystal display panel according to claim 3, wherein the metal wire grid structure is made of a metal of Al, Mo, Au, Cr or an alloy material thereof.
The liquid crystal display panel according to claim 2, wherein the metal wire grid structure is a single-layer metal wire grid structure or a double-layer metal wire grid structure.
The liquid crystal display panel according to claim 7, wherein in the single-layer metal wire grid structure, at least two metal strips extending in parallel in the same direction are disposed on a surface of the color filter substrate, adjacent to each other. The metal strips are separated by a wire gap,

The metal strips have the same height in a direction perpendicular to the surface of the color filter substrate.
The liquid crystal display panel according to claim 7, wherein in the double-layer metal wire grid structure, at least two metal strips and dielectric strips extending in parallel in the same direction are disposed on a surface of the color filter substrate. And the metal strip and the dielectric strip are staggered without gaps, and the metal strip is covered with a metal strip on the surface of the dielectric strip remote from the color filter substrate.
The liquid crystal display panel according to claim 9, wherein the film is perpendicular to the color filter substrate In the direction of the surface, the metal strips have the same size, and the height of the dielectric strip is greater than the size of the metal strip.